Training might teach the brain to prefer healthy food

It may be possible to train the brain to prefer healthy low-calorie foods over unhealthy higher-calorie foods, according to new research.

“We don’t start out in life loving French fries and hating, for example, whole wheat pasta,” said Susan B. Roberts, director of the Energy Metabolism Laboratory at the U.S. Agriculture Department’s Human Nutrition Research Center on Aging. “This conditioning happens over time in response to eating – repeatedly!—what is out there in the toxic food environment.”

Roberts is senior author of the study, published online Sept. 1 in the journal Nutrition & Diabetes. The findings suggest one could reverse the addictive power of unhealthy food, the investigators said.

They enrolled 13 overweight and obese adults for the study, eight of whom joined a new weight loss program designed by researchers at Tufts University in Boston. The program included behavior change education and high-fiber, “low-glycemic” menu plans. Low-glycemic foods are ones that don’t abruptly affect blood sugar levels.

Both groups underwent brain scans at the beginning and end of a six-month period. Among those who underwent the weight loss program, the brain scans revealed changes in areas of the brain reward center associated with learning and addiction, the researchers said. After six months, they added, this area showed more sensitivity to healthy, lower-calorie foods, and less sensitivity to the unhealthy higher-calorie foods.

“The weight loss program is specifically designed to change how people react to different foods, and our study shows those who participated in it had an increased desire for healthier foods along with a decreased preference for unhealthy foods, the combined effects of which are probably critical for sustainable weight control,” said co-author Sai Krupa Das, a scientist in the Energy Metabolism Laboratory at the center. “To the best of our knowledge this is the first demonstration of this important switch.”

“Although other studies have shown that surgical procedures like gastric bypass surgery can decrease how much people enjoy food generally, this is not very satisfactory because it takes away food enjoyment generally rather than making healthier foods more appealing,” added co-author Thilo Deckersbach, a psychologist at Massachusetts General Hospital.

“There is much more research to be done here, involving many more participants, long-term follow-up and investigating more areas of the brain,” Roberts said. “But we are very encouraged that the weight loss program appears to change what foods are tempting to people.”